1. Field of the Invention
The present invention relates to a pneumatic tire used together with a standard wheel rim, more particularly to an improved sidewall structure which can minimize bead unseating during the use of the tire, especially in the uninflated state.
2. Description of the Related Art
If the inner pressure of tire is decreased due to punctures and the like, the bead portions of the tire easily dislocate from the bead seats of the wheel rim and, at worst, the bead portions get over the rim flange.
In order to avoid such a dangerous situation, a special wheel rim has been proposed. However, in such a special wheel rim, it is difficult to mount and demount the tire. Therefore, the special rims hardly~come into the market.